RF transmitters include AM, FM and TV transmitters. Such transmitters typically include a group of RF amplifiers and power supplies with a plurality of components. Such a transmitter has different operational modes. Some systems have a very sophisticated turn-on and turn-off process or sequence. The sequence may include a dozen or more steps or stages and the operation will be switched from one state to another during the process. The timing between the various states of operation may be very critical; otherwise it may cause damage to the system. A typical IOT (Inductive Output Tube) transmitter, for example, may include a plurality of states such as four main states and each main state may have several sub-states such as fourteen sub-states. These sub-states operate the on, off or standby processes as the system advances from one state to another in precise timing. The processes may be interrupted by an external event such as a command or one of many possible faults.
It is desirable that all state transition and mode switching be recorded along with the time of happening for system operation diagnosing and monitoring. All commands or faulty events that happen during the operation to cause system state change should be recorded with the time of occurrence. The recording (or logging) could record operator activities on the system operation, such as issuing a command to turn on or off the system or the subsystem or to raise or lower the power or to switch exciters.